黄土路堑边坡开挖变形机理的离心模型试验研究

利用离心模型试验揭示了黄土路堑边坡在开挖过程中的变形破坏特征,结果表明:开挖前,坡体变形以自重应力作用下的竖向变形为主,开挖后,堑坡坡体中后部土体以垂直向下变形为主,前部土体变形以水平变形为主,而且坡体前部的变形远大于中后部的变形;同时结合变形特征,系统分析了黄土路堑边坡开挖过程中主滑段滑带土的强度变化规律,认为黄土路堑边坡开挖变形破坏的力学机制总体上应属于蠕滑-压致拉裂机制。

Centrifuge model test on the deformation mechanism of loess cut slope

The deformation characteristics of loess cut slope are demonstrated by centrifuge model test.The results show that the vertical deformation under the self-weight stress is dominant for the whole loess slope before excavation.But after excavation,the deformation of the front and middle of cut slope gradually change from vertical to horizon.The deformation of the back of cut slope is as same as before,but the deformation of the front part is much greater.Meanwhile,combined with the deformation characteristics obtained from the model test of loess cut slope,the paper systematically analyzes the strength varies of the major slip band during the excavating of loess cut slope,and considers that the deformation mechanism of loess cut slope belongs to creeping slide and crack arising from pressing.